Before I can answer your question, I need to know what you actually mean by the word “spaces.”
Let’s make something abundantly clear: Trans people have zero interest in making friends with bigots. If you want to make a cis-only Sunday bowling group or whatever, be my guest. I truly do not care, and have absolutely zero interest in being a part of that shit. But own up to what you’re doing and call it a cis women only group instead of twisting yourself into a pretzel to exclude one particular adjective from the noun to which it’s attached.
What the “womyn-born-womyn” types often do instead is place themselves in positions of crisis resources, dropping a byline about how they support “trans resources” without ever actually committing money to get them started up. As a result, despite being at risk for all the same violence as cis women, trans women are often excluded from these crisis resources and have to deal doubly with the oppression from violence by men and institutional hostility from resources to recover from it created by trans-exclusionary ontologies. That is considerably harder to justify and I have never once seen a “cis-women-only” type actually do this a way that was both logically cogent and empirically supported.
that trans women have privileges from having been brought up as boys
No, because the notions of male and female privilege were never conceived to account for what trans people actually deal with. Given that trans women experience violence at greater rates than cis women, I can’t possibly understand how you could assert that trans women retain male privilege, even if I were to accept the premise that we were once the beneficiaries of it (which I don’t).
that cis women have a right to talk about how their female bodies shape their experiences of oppression?
Sure? I honestly don’t know what the hell you’re talking about with this word salad. Don’t all bodies shape our experiences of oppression?
You’re going to have to point me to some specific material because this sounds like you’re getting ready to shovel a bunch of straw in my mouth.